Rope-clamp



0. CROSBY. ROPE CLAMP.

APPLICATION FILED MAY26| 919.

Patented Apr. 5, 1921.

LS?398OGD clamp, before the U-bolt is tightened, showf omvnn cnosnY, or ST. PAUL, mmnrso'ra, assrenon 'ro Amnnrcm nors'r & DERRICK 00., or s'r. mun, mnmnso'rs, A rn'rivnnsnm Born-e.

To all'whomitma concern:

Be it known t at I, OLIVER 'CRosBY, acitizen of the United States, resident of St. Paul, county ofRamsey, State of Minnesota, have invented certain new and useful Improvements in nope-Clamps, of which the following is a specification.

My invention relates to ent of the United States No. 1,271,284, issued to the American Hoist & Derrick Co., the assignee, the 2nd day of July, 1918.

The object of my present invention is to provide a U-bolt having a broader, flatter bearing surface than usual in rope clamps of this kind to the end that the U-shaped portion of the bolt will have a firmer, better bearing on the cable and be more likely to hold the cable securely against slippage.

A further object is to provide a clamp in which the body-portion thereof is provided with a comparatively large area for contact with the rope to be clamped.

Other objects of the invention will appear from the following detailed description.-

The invention consists generally in various constructions and combinations, all as hereinafter described and particularly pointed out in the claims.

In the accompanying drawings forming part of this specification,

Figure 1 is a view, partially in section, showmg by improved clamp in position for use,

Fig. 2 is a sectional view through the ing the broad flat bearing surfaces between which the rope or cable is gripped and held,

Fig. 3 is a similar view of the clamp showing the position of the lugs thereon arranged in pairs upon opposite sides of the U-bolt,

Fig. 4 is a sectional view through the U- bolt, showing the broad flattened bearing surface at the bend of the bolt,

Fig. 5 is a plan view showing the relative position of the lugs on the base of the body of the clamp.

In the drawing, 2 represents the U-shaped portion of the clamp. This is preferablyformed by bending a straight piece of metal and prior to the bending operation the surface of the piece of metal, preferably near the middle thereof, is flattened and pressed outwardly by means of a sultable die to Specification of Letters Patent.

. tact. that class of rope. .clamp shown and described inLetters Patform a broad surface 3 midway betweenthe ends of the U-bolt, and the pressure of the die forces the metal outwardly on each side, as indicated at 4 in Fig. 4, thereby considerably increasing the area of the surface of the bolt with which the cable comes in con- Obviously, where there is frictional engagement between two members, the greater the area of the bearing surface the greater the friction and the more securely the lapping ends of the cable will be held. In this particular case the die is preferably fashioned to press the metal outwardly; on

each side, as shown in Fig. 4, and on'the flattened surface 5 of the bolt I provide a series of ribs 6 which are adapted to fit the lay of the rope or cable; that is, when the bolt is moved to its clamping position the obliquely arranged ribs will register with the depressions or. grooves running diagonally of the surface of the rope or cable and serve as an effective means for preventing slippage when the rope is subjected to strain. I regard'this flat surface intermediate to the arms of the U-bolts as an important feature of my present invention, as usually the U-bolt at the bearing point is round in cross section and has only a comparatively small bearing onthe rope or cable.

7 represents a block forming the base of r the clamp having holes 8 therein to receive the arms 9 of the U-shaped bolt, said arms being threaded to receive lock nuts 10 which when turned up against the under surface of the block will firmly grip the U-bolt with the cable and prevent slippage thereon. On each side of the U-bolt, projecting upwardly from the base, is a lug 11, there being preferably four of these lugs for each base, sufficient space being provided between the lugs to receive the ends of the cables to be joined and form hearings or stops against which the arms of the bolt are seated when the clamp is under a severe strain. I prefer to arrange these lugs so that the bolt will be supported thereby and will not be bent or twisted out of its normal position or shape when subjected to severe strain. As

Patented Apr. 5, 1%21. Application filed may 26, 1919. Serial Ho. 299,684. i

heretoforestated, the broad bearing surface of the bolt is formed by the pressureof a die on the metal bar of which the bolt is composed, such pressure being suflicient to spread the metal outwardly and form bosses or extensions on each side of the bolt and. atthe'same time materially increase the area the cable but the bend or kink in the cable to fit into the depression of the base 7 is omitted, as this would only appear when they nuts of the U-bolt are tightened and the cable securely gripped.

The base 7, preferably of a drop forging, is provided with a' surface 12 for contact with the cable, having ribs 13 running diagonally thereof and preferably slightly concave so that when pressure is applied by the U-bolt, the cable will be bent into the concave and kinked slightly, making it less likely to slip in the clamp. The ribs 13 are formed to fit the surface of the rope or cable in the same manner as described with reference to the ribs of the U-bolt and I have found that by making these ribs or corrugations gradually fit the twist of the rope there is less danger of damage to the rope and the clamp holds it more securely.

This concave feature of the base may, however, be omitted, if preferred, and the surface may be made fiat or any suitable shape to fit the surface of the cable seated thereon, the essential feature of my invention being the formation of the bolt with the broad, flattened bearing surface of the cable. This broad surface through its ribs or corrugations firmly engages the surface of the cable and locks it securely agalnst slippage and thereby the value of the device as a rope clamp' is considerably enhanced.

I claim as my invention: a

1. A rope clamp comprising a U-shaped bolt, a block slidable thereon, clamping nuts for the ends of said bolt, the curved or middle portion of said bolt having a broad flat tened surface formed thereon for contact with the cable to be clamped. I

2. A rope clamp comprising a U-shaped bolt, a block slidable thereon, clamping nuts for the ends of said bolt, the curved or middle portion of said bolt having a broad flattened surface formed thereon for contact with the cable to be clamped, said surface having ribs or corrugations extending obliquely thereon. v 3. A rope clamp comprising a bolt to straddle the cable to be clamped, a block slidable on the ends of said bolt, clamping nuts for said ends, said block having a comparatively broad clamping surface with diagonal ribs formed therein and said surface being concave. j

4. A rope clamp comprising a U-shaped bolt, ablock slidable on the arms thereof, clamping nuts for the arms of said bolt, the curved middle portion of said bolt having a surface of greater width than the normal diameter of the bolt, said surface being formed by the pressure of a die thereon, the

rope or cab-1e tobe clamped being held be:

tween said surface and said block.

5. A rope clamp comprising a U-shaped bolt, a block slidable on the arms thereof, clamping nuts for the arms of said bolt, the curved middle portion of said bolt having a surface of greater width than the normal diameter of the bolt, and said block having a surface cooperating with the surface on said bolt to grip the rope or cable between them.

In witness whereof, I have hereunto set my hand this 22nd day of May 1919.

OLIVER o tosBY Witnesses:

O. W. MORTON, E. M. BOEGE. 

